Bitumen Binders Modified with Sulfur/Organic Copolymers

Abstract

With the continuing growth of waste sulfur production from the petroleum industry processes, its utilization for the production of useful, low-cost, and environmentally beneficial materials is of primary interest. Elemental sulfur has a significant and established history in the modification of bitumen binders, while the sulfur-containing high-molecular compounds are limited in this field. Herein, we report a novel possibility to utilize the sulfur/organic copolymers obtained via the inverse vulcanization process as modifiers for bitumen binders. Synthesis and thermal characterization (TGA-DSC) of polysulfides derived from elemental sulfur (S8) and unsaturated organic species (dicyclopentadiene, styrene, and limonene) have been carried out. The performance of modified bitumen binders has been studied by several mechanical measurements (softening point, ductility, penetration at 25 °C, frass breaking point, adhesion to glass and gravel) and compared to the unmodified bitumen from the perspective of normalized requirements concerning polymer-modified bitumen. The interaction of bitumen binder with sulfur/organic modifier has been studied by means of FTIR spectroscopy and DSC measurements. The impact of the modification on the performance properties of bitumen has been demonstrated. The bitumen binders modified with sulfur/organic copolymers are in general less sensitive to higher temperatures (higher softening point up to 7 °C), more resistant to permanent deformations (lower penetration depth), and more resistant to aging processes without intrusive deterioration of parameters at lower temperatures. What is more, the modification resulted in significantly higher adhesion of bitumen binders to both glass (from 25% up to 87%) and gravel surfaces in combination with a lower tendency to form permanent deformations (more elastic behavior of the modified materials).

Rheological and Aging Characteristics of Polymer-Modified Asphalt with the Addition of Sulfur

“…Following the polymer addition, the mixture was mechanically agitated using an IKA RW 20 mixer for 60 min at 1500 rpm to make the blend essentially homogeneous. Subsequently, the PMA was prepared by mixing it with a calculated sulfur content, including ratios of 0.075%, 0.03%, 0.1%, 0.3%, and 0.5% by weight of binder [9,16,24,26,40,41]. These specific ratios were chosen based on pre-screening tests, which indicated their suitability for the study, and the selection aligns with findings from relevant research.…”

Effect of Bisphenol-Formaldehyde Resin on Physico-Mechanical Properties of Road Bitumen

“…An effective way to solve this problem is to improve the structure and properties of bitumen by using inexpensive modifiers of various types. [1][2][3][4] The processes of modification of oil residues are divided into physical and chemical. Physical modification of oil residues involves the introduction of various types of applications into their composition, which ensure improvement of operational characteristics.…”

Feasibility Investigation of Bitumen Properties by Blending of Coal Tar Pitch

“…Coal tar pitch has been widely explored and employed as a bitumen modifier due to their various functional groups. Low-molecular organic molecules (formaldehyde and maleic anhydride) [17] [18] and sulfur/organic copolymers [19] are generated as byproducts of coal conversion. G. Strap et al [20], and M. Çubuk, et al [21] found out that phenol-formaldehyde resins can be fairly effective petroleum bitumen modifiers.…”